The present invention relates to a method and apparatus for interconnecting two components with a helical extension spring.
To stretch or load a helical extension spring between two components, the helical extension spring should be expanded to a required length so as to tension one component against the other component to which the first component is to be fitted for relative movement. The helical extension spring has heretofore been held between hooks and expanded to a required length by displacing the hooks apart from each other. Such a spring fitting method and an apparatus therefor is known from Japanese Patent Publ. No. 57-46980 (1982) or Japanese Unexam. Patent Publ. No. 61-95837 (1986).
It is thus generally known to expand and attach a helical extension spring between two components one of which is to be spring urged so as to be movable relative to the other component. In conventional methods, the component to be spring urged is first attached to the other component and thereafter, the helical extension spring is stretched and attached to the two components.
Before attaching the expanded helical extension spring to the two components, one of the two components has to be firmly held relative to the other component. For this purpose, it is necessary to use a holding jig or fixture, which results in an inferior operating efficiency and an inferior degree of fitting reliability.